X-ray radiator with thermionic emission of electrons from a laser-irradiated cathode

An x-ray radiator comprising:

• an evacuated housing mounted for rotation around an axis;
• a cathode disposed in said housing;
• a laser source that emits a laser beam from a stationary location outside of said vacuum housing onto a spatially stationary laser focal spot on said cathode, said laser source emitting said laser beam with a laser power that heats said cathode to cause said cathode to thermionically emit electrons;
• an anode disposed in said housing on which said electrons are incident that emits x-rays upon being struck by said electrons;
• an insulator forming a part of said vacuum housing that separates said cathode from said anode;
• terminals for application of voltage between said anode and said cathode to accelerate said electrons from said cathode toward said anode as an electron beam;
• a drive in driving engagement with said housing to rotate said housing around said axis;
• and
• a cooling arrangement in thermal communication with at least one of said anode, said cathode and said housing to conduct heat therefrom.